Duckbill catheter release mechanism

Abstract

A needle guard includes a clip with a canting wall to grip the needle shaft and a distal wall to block the tip thereof, wherein the canting and distal walls may be interconnected by an angled strut, a spring member, such as a leaf spring, may have a portion extending past an edge of the strut to bias the clip to grip the needle shaft, and the distal wall may be or include a stylus and have an L-shape to define a lip to help block the needle tip. The clip may have a depending heel to help pivot the clip about a ledge to grip the needle shaft. A needle support may be provided to limit flexure of the needle which might otherwise allow the needle to come loose from the clip. Arrangements for limiting rotation of the needle hub and needle guard housing are provided, as is a protective shroud to reduce the risk of inadvertent activation of the needle guard. Further, the needle guard may be used with a catheter assembly. Also provided is an improved duckbill release mechanism.

What is claimed is: 
     
       1. A safety catheter device comprising:
 a catheter hub having an interior surface and a generally annular rib projecting radially inwardly from the interior surface; 
 a catheter tube extending from a distal end of the catheter hub; 
 a needle hub and a needle having a shaft extending therefrom to a sharp distal tip; and 
 a housing removably coupled to the catheter hub and adapted to slidably receive the needle shaft therethrough between a first position with the needle distal tip exposed and a second position with the needle distal tip protected, the needle shaft being held in the second position by an active element in the housing gripping the needle shaft, the housing including a pair of cooperating members extending to distal ends and defining a passageway therebetween, a portion of the passageway extending between the distal ends, the passageway being nominally sized along its length to slidably receive the needle shaft freely therethrough, at least one of the members including a detent element adapted to cooperate with the rib of the catheter hub to rotatably and releasably hold the housing to the catheter hub, such that the detent element releases from the rib by compression of the at least one member to narrow the passageway, and wherein presence of the needle shaft in the passageway limits such compression to thereby restrict release of the housing, the needle hub being spaced and uncoupled from the housing other than via the needle shaft being gripped by the active element in the second position. 
 
     
     
       2. The safety catheter device of  claim 1 , each member including a detent element adapted to cooperate with the rib of the catheter hub. 
     
     
       3. The safety catheter device of  claim 2 , each detent element being on the distal end of the respective member. 
     
     
       4. The safety catheter device of  claim 3 , the detent elements cooperating to define segments of an annular ring. 
     
     
       5. The safety catheter device of  claim 2 , the detent elements cooperating to define segments of an annular ring. 
     
     
       6. The safety catheter device of  claim 1 , the detent element defining an annular ring segment. 
     
     
       7. The safety catheter device of  claim 1 , wherein the members define a split cylinder. 
     
     
       8. The safety catheter device of  claim 1 , the rib being continuous. 
     
     
       9. The safety catheter device of  claim 2 , the interior surface of the catheter hub having a proximal tapered portion, the rib being distal thereof. 
     
     
       10. The safety catheter device of  claim 9 , the tapered portion having a minimum inner diameter generally not less than a maximum outer diameter defined at the detents. 
     
     
       11. The safety catheter device of  claim 1 , the rib being discontinuous and having gaps that are smaller than a circumferential width of the detent. 
     
     
       12. The safety catheter device of  claim 1 , at least one member including an internal ridge to define the size of the passageway. 
     
     
       13. The safety catheter device of  claim 1 , each member including an internal ridge to define the size of the passageway. 
     
     
       14. The safety catheter device of  claim 1 , the needle shaft having a generally constant diameter along its length, the size of the passageway being closely dimensioned to the diameter of the needle shaft. 
     
     
       15. The safety catheter device of  claim 1 , the interior surface of the catheter hub having a proximal tapered portion, the rib being distal thereof. 
     
     
       16. The safety catheter device of  claim 15 , the tapered portion having a minimum inner diameter generally not less than a maximum outer diameter defined at the detent. 
     
     
       17. The safety catheter device of  claim 1 , further comprising an active element within the housing to protect the tip of the needle when the tip is within the housing. 
     
     
       18. The safety catheter device of  claim 1 , the needle hub including a shroud sized to overlie opposed portions of the housing when the needle extends through the housing, catheter hub and catheter tube such that the needle tip extends out from the catheter tube, and to be spaced from the housing otherwise, and a sheath enclosing at least the catheter tube and the needle tip, and overlying at least a portion of the shroud. 
     
     
       19. The safety catheter device of  claim 1 , the needle hub and the housing including cooperating structure to hold them against relative rotation when they are in adjacent relationship. 
     
     
       20. The safety catheter device of  claim 1 , further comprising a needle support within the housing adjacent a plane transverse to a cylinder of the needle shaft. 
     
     
       21. The safety catheter device of  claim 1 , the cooperating members being arcuate in cross-section and including a respective internal ridge sized in relation to a needle. 
     
     
       22. A method of obtaining generally consistent removal forces of a duckbill release mechanism across a range of needle gauges comprising:
 providing a pair of generally arcuate cross-section coupling members extending from a nose portion of a housing and sized to be received within a catheter hub; 
 providing on each coupling member an internally depending ridge having a radial depth related to the gauge of a needle with which it is to be used, such that clearance in a predetermined range is defined between the ridges and the needle extending therebetween. 
 
     
     
       23. The method of  claim 22 , wherein the internally depending ridge is axially elongated and extending between proximal and distal ends of the coupling member. 
     
     
       24. The method of  claim 22 , wherein the internally depending ridge includes a side edge that is spaced from an inner wall of the arcuate cross-section coupling member.